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Wilkinson, Geoffrey W
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V/ilkinson, Geoffrey W
Comnon hazards. By Geoffrey W. Wilkinson...
London, Layton, 1922.
xvii, 38 p. l&h cm.
Bibliographical note: p. j-iii^-iv.
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GEOFFREY W. WILKINSON
Auihor of "Fire Re-mMurance,"
CHARLES & EDWIN
56, Farringdoa St , , E C . 4 .
School of Business
•tamped below, and if not returned or renewed at or
before that time a fine of five cents a day will be incurred.
GEOFFREY W. WILKINSON,
Author of " Fire Re-insurance."
CHARLES & EDWIN LAYTON,
56, Farringdon Street, E.G. 4.
Young students of " Common Hazards " must
often have felt the lack of a text book on their
subject. I felt it myself many years ago before
I sat for the " Chartered Insurance Institute "
Examination, and strange to say, so far as I know,
though I may be wrong, no such text book has yet
appeared. If I have succeeded in filling the want
to a certain extent I shall be glad. Even in that
case, however, the credit will only be mine to a
small extent. For I am greatly indebted to
many writers of papers and notes on the subject
of " Common Hazards," and I must at once
acknowledge my indebtedness to several gentlemen
from whose papers I have made quotations.
Foremost among these I must mention Mr. W.
Carter, whose paper on Common Hazards is
recognised as the standard reference. Mr. T.
Healey's paper on The Fire Risks in Artificial
IlluminantSy read in the year 1914, is also of
great value, while Mr. J. H. Matthew's Essay on
Building Construction in Relation to Fire Hazard,
published in booklet form, is uncommonly
interesting to the student either of " Common
Hazards " or " Building Construction." I should
almost mention my indebtedness to the Post
Magazine and Stone & Cox's Fire and Marine Year
In writing my notes on the various items of
risk I have aimed at condensation rather than a
fluent style, and the result may be considered
somewhat patchy, but I would recommend the
student to supplement his reading of them by the
perusal of as many as possible of the excellent
papers which are given from time to time by
G. W. Wilkinson.
Leeds, ^h February, 1922.
TABLE OF CONTENTS.
Cubical Capacity .;.
Extensive Floor Space
Exposure 17, 18, 19, '
Too Much Window
28, 29, 30.
Lack of Fire Brigade
Well Holes ...
Xa^£M1S£S ••• •••
/VR£AS ••• •••
WITH Matches ...
Lights Thrown Down
Heating 38, 39, 40,
Treading on Unused
43. 44. 45.
Lighting 48, 49, 50,
Gas Engines ...
Common Hazards is the title given, by the
Chartered Insurance Institute of Great Britain
and Ireland, to one division of technical knowledge
in which candidates for their diploma are
Except to those having some experience of
the Fire Insurance business, the name gives no
clear indication of the category of human
knowledge which the subject embraces. Unlike
the great majority of subjects, with the names
(at least) of which every schoolboy is familiar,
" Common Hazards *' is a subject the limits of
which, at any rate for the purposes of the
Chartered Institute examination, are arbitrarily
fixed. To take another subject by way of
contrast, Electricity, for instance, is a branch of
science which depends for its existence on a
diistinct class of natural phenomena, and every
student knows that anything connected with the
electrical fluid appertains to the science of
Electricity ; but as regards " Common Hazards,"
although we can easily state whether or not a
circumstance comes in that category when we
know tJie exact scope of the subject, the title itself
is not a key to the classification. It is for those
who affix the title to indicate the hmits of the
I think it may be safely asserted that these
limits have not yet been clearly defined; but,
for all practical purposes, the scope of the subject
to be studied by those who wish to pass the
Chartered Institute's examination can be clearly
enough apprehended from the questions asked
and from the published syllabus.
Quite apart from the Chartered Institute
Examination, the term " Common Hazards "
suggests to the Fire Insurance official those
commonly occurring circumstances which may : —
[a) Give rise to fires (i.e,, direct causes of
fires) as, for instance, the throwing down
of lighted matches.
(h) Tend to increase the loss caused by fire as,
for instance, the excessive height of
(c) Increase the probabihty of fires occurring
as, for instance, the proximity of wood-
work to a gas Hght.
But how common a hazard has to be before it
can be considered as coming within the limits set
by the Chartered Institute is a moot point.
In writing these notes, however, I have tried to
include all the " Common Hazards " that are
likely to come within the scope of the examination
and, in addition, to treat the subject in such a
way that the student may acquire more knowledge
of it than that which might enable him to pass
the examination. The passing of the latter is
after all only an incentive to the study of Fire
Hazards, and it is the dissemination of knowledge
on this subject and the encouragement of research
that are of value rather than the granting of
certificates to individuals. Let the individual
student grasp the essentials .of the subject and he
will soon find himself, if he wishes, in possession
of the Chartered Institute certificate.
The study of Fire Hazards is indeed of
immense importance : this will be realised when
it is known that the loss caused by Fire in Great
Britain alone amounts to a figure in the neighbour-
hood of £10,000,000 annually. Many of the
subjects set by the Chartered Insurance Institute,
though important to the Insurance official because
the studying of them assist him in the efficient
execution of his work, are of little direct interest
to the community at large : " Common Hazards,"
on the contrary, are a menace to the community
and, as such, call for careful attention from those
whose duty it is to protect the community from
For convenience of study it is advisable to
make some divisions of the subject.
. As stated on page viii, '* Common Hazards "
may be divided into three categories which are
here repeated, viz. : —
(a) Those which may give rise to fires.
(b) Those which tend to increase the loss
caused by fire.
(c) Those which increase the probability of
It may be necessary to point out, however, to
the young student that though the hazards in
these three categories may not be of equal
importance, the difference in importance of any
two of them does not necessarily arise from the
fact that one is in one of the above categories
and the other in another. It is true that without
the hazards in category (a)— the direct causes of
fires — ^no fire losses would occur, but, on the other
hand, many fires are caused without resulting in
any great loss of property. In the absence of the
conditions referred to in category (b) — hazards
which tend to increase the losses caused by fire —
many fires may occur without causing any
considerable loss. Let us take a concrete example
to show, perhaps more clearly, what is meant.
Imagine a five-storeyed building of non-
fireproof construction, the ground floor of which
has a wooden ceiling and is hghted by unprotected
incandescent gas-lights of high candle power, the
lamps being near the ceiling.
If this is a complete description of the building,
the latter cannot catch fire unless the gas is
lighted : a young student might therefore think
that the most important hazard in the building
was the gas-light ; and he might argue that, if
you could prevent the direct causes of fire such as
uncovered lights, you would prevent all
destructive fires and that therefore the Fire
Insurance Surveyor ought to concentrate his
attention on the causes of fires.
This is not exactly the case, however. It
must be remembered that while it is impossible to
prevent all causes of fires, the Insurance Com-
panies are more concerned with the amount of
loss caused through property being burned than
with the frequency of fires. An Insurance
Company would prefer to have a thousand fires
which caused a loss of a pound or two each,
rather than one fire which caused a loss of (say)
£10,000. The extent of fire losses, not the
frequency of losses, is what the Surveyor has
above all to guard against.
In the hypothetical building cited above, there
are three hazards requiring the Surveyor's atten-
tion and each of these comes within a separate
category as above defined. They are as follows,
viz. : —
(a) The incandescent gas-lights, being of high
candle power and yet unprotected.
(b) The height of the building, because of the
tremendous up-draught of air which
would be caused if a fire arose, and
because of the difficulty met by firemen
in squirting water to the top of high
buildings, and for other reasons (see
(c) The proximity of wooden ceilings to the
lights, thus making a fire more probable.
This example may help the student to realise
that in studying " Common Hazards " it might
be easy for him to exaggerate the importance of
direct causes of losses. Constructional hazards
and a multitude of other kinds of hazards are just
as important as those which refer immediately to
the existence of flames, sparks, or electrical
currents. The student of " Common Hazards "
has to learn, not only the causes of fires, but a far
greater subject — the causes of fire-losses.
The multifarious nature of the causes of fire-
losses baffles our efforts to make a simple and yet
comprehensive classification which should indicate
the comparative importance of the hazards.
Nevertheless the student may well' call for some
guidance as to which kinds of hazards are most
productive of fires, which really are the common
hazards, and what divisions of the subject he can
make for the sake of convenience of study. In
accordance with these requirements, the scheme I
have borne in mind in writing these notes is to
make five broad divisions of " Common Hazards "
thus : —
I. Hazards of Lighting.
II. Hazards of Heating.
III. Constructional Hazards.
IV. Exposure Hazards.
V. Miscellaneous Hazards.
On glancing through paragraphs i to 54,
however, the reader will notice that I have not
strictly observed the above order in dealing
separately with the hazards. I have deliberately
done otherwise partly to make the reading, as
well as the writing, of the notes more interesting,
and partly because I think some advantage may
be gained by dealing with some of the mis-
cellaneous Hazards at an early stage. The
hazards of Height, Night- work. Cubical Capacity,
for instance, are selected for mention in the
Syllabus of the Chartered Institute's examination,
and might well be recorded near the beginning
rather than the end of the notes.
Of these five categories the most important is
that which refers to Hazards of Lighting. Accord-
ing to the Chief Officer of the London Salvage
Corps, 753 fires out of a year's total of 3,3^7 ^vere
caused by Lighting Hazards in London. That is
22-2 % were caused by Artificial Lighting.
Paragraphs Nos. 48, 49, 50, 51 and 52, refer to
It is probable that Hazards of Heating come
next to those of Lighting in importance and
these are dealt with in paragraphs Nos. 38, 39, 40,
41, 42, 43, 44, 45, 46 and 47.
Hazards of Construction require a very con-
siderable amount of study. There are so many
frequently occurring constructional defects to be
noticed by one who is estimating comparative
fire-risks that it is fortunate for me that I have
set out to enumerate Common Hazards only, that
is to say only the more important and frequently
occurring hazards. To indicate all types of
defective construction would be, not only to
encroach on but actually to encompass the whole
subject of Building Construction as understood by
the expert in Fire Prevention. That is not the
present writer's duty ; what he has to do is to
include, in his hst of commonly occurring hazards,
those features of construction which are excep-
tionally undesirable from a Fire Insurer's point
of view, but which are nevertheless frequently
foimd in buildings.
Constructional Hazards are considered in
paragraphs 25, 26, 27, 28, 29, 30, 31 and 32.
Exposure Hazards are hazards that are due
to the proximity of buildings or parcels of property
one to another. A non-fireproof building near
another non-fireproof building is exposed to fire-
hazard from the latter. The degree of risk which
one building entails upon another depends very
greatly upon their relative heights : a high building
is more liable to communication of fire to it from
an opposing low building than a low building
from a high one ; because the natural direction
of flames is upward. The risk depends also upon
their distance apart and upon their construction.
It also depends upon the existence, size, etc., of
openings in the walls of the buildings and upon
the slope of the ground.
But it is the importance of construction that
should be specially emphasized in connection
with exposure. A building that carries external
timber fixtures may be exposed to a fire-hazard
from neighbouring or adjoining buildings, or it
may not ; but in either case, from the Fire
Insurer's point of view, it is an instance of defec-
tive construction. But where there are buildings
adjacent or near to a building having woodwork
on its exterior, the exposure hazard to the latter
is considerably increased ; and even if such a
building stands quite alone its partial timber
construction is a risky feature. The use of
timber or other inflammable material on the
outside of buildings therefore introduces either
one hazard, viz. : defective construction ; or two
hazards, viz. : defective construction and exposure
Paragraphs Nos. 17, 18, 19, 20, 21, 22 and 23
deal with Exposure hazards, but most of them
are also concerned with Constructional Hazards.
Now I want to emphasize a fact which should
be duly noted by the young student, if it has not
already occurred to him — a. fact which in any case
he should continually bear in mind.
This is, namely, that a conflagration is a
phenomenon of enormous destructive power which,
under certain circumstances, can reach such a
degree of intensity as to devour nearly all that
comes in its path. It can make masonry crumble
and collapse ; it can twist heavy ironwork into
fantastic shapes ; corrugated iron can withstand
it little better than a wooden partition ; slates
crack under its heat.
The student must learn to estimate risks with
this in his mind. An uncovered iron girder may
seem to him a harmless feature ; but let him see
how a conflagration can rive such a girder from
its position, and in so doing cause the collapse of
a wall, and he will realise that the girder should
be covered with terra-cotta, concrete or plaster.
A wooden gutter running along the eaves of a
street-building may seem to him an insignificant
risk ; but let him see the flames from a
conflagration darting in the wind from gutter to
gutter, even across streets, withdrawing the
firemen's attentions from the centre of the fire,
and perhaps giving rise to additional con-
flagrations, and he will agree that gutters should
be made of metal. Let him bend back his head
and gaze up at firemen, small in perspective,
working at the top of a high building on fire, and
he will begin to appreciate the hazard of height.
Let him watch the strenuous efforts of firemen to
prevent a huge fire spreading to an adjoining or
neighbouring building, and he will begin to
admire the qualities of fireproof construction.
Let him remember that the most powerful enemy
of fire is — ^bricks.
By way of concluding this introduction, I
have added a summary of the paragraph headings
arranged in such a way as to indicate, at a glance,
the ground covered by this little book.
ExTKNsivE Floor Space
Exposure 17, 18, 19,
Too Much Window
28, 29, 30,
Lack of Fire Brigade
Well Holes ...
x\ xvc« A • • • • a •
JrRSBillSCS ••• •••
WITH Matches ...
Lights Thrown Down
Heating 38, 39, 40,
43. 44. 45.
Treading on Unused
Lighting 48, 49, 50,
Gas Engines ...
Depositing Ashes ...
1. Height. — Fire has a natural tendency to
spread in an upward direction even more easily
than laterally ; and just as a building containing
a large undivided floor space is considered (as
such) a worse risk than a small building, so a high
building is considered more hazardous than a low
A building with more than one storey is made
more hazardous by each additional storey and as
a rule, each storey above a reasonable number
gives rise to an additional rate of premium on the
building and its contents.
For, in case of fire, the up-draught of air
through floor communications is intensified in a
high building ; and unless hoists and staircases
are enclosed by walls of brick or other incombus-
tible material, with a fireproof door to each of the
openings, they provide easy conveyance of flames
from floor to floor.
If a building is five or six storeys in height.
Fire Brigades would have difficulty in coping with
2 COMMON HAZARDS.
a fire in the upper storeys. Sixty feet is the
greatest height to which a building can be quickly
protected by the Fire Brigades even in London
(1910), and lower buildings will present difficulties
to many provincial brigades.
Additional reasons for an increase in premium
on account of excessive height are (i) that plural
tenancy is more likely in a building with many
storeys, (2) that with each additional storey the
risk of collapse of the walls is increased by the
added weight on the floors, (3) that several high
buildings near to one another increase the exposure
hazard. (See paragraphs 6 & 17.)
2. Cubical Capacity. — Separate parcels of
property, say, for instance, pieces of woollen cloth,
are not so likely to be damaged by fire if they
are separated from each other by party walls as
they would be if they were almost touching each
other in the same room. The more a thousand
pounds worth of cloth is divided up in such a way
as to avoid fire leaping from one part of it to
another, the less risk there is of that thousand
pounds worth of cloth being destroyed by fire.
Conversely a large accumulation of property
in one building is necessarily rated higher than the
same property would be if it were divided up in
several smaller buildings — hence the extra rate
charged for excessive cubical capacity in Woollen
and other Warehouses and Furniture Depositories.
COMMON HAZARDS. 3
In Cotton Mills the number of spindles used are
taken as a criterion of size ; in Corn Mills the
amount of roller contact.
3. Extensive Floor Space. — " Extensive floor
space, unbroken by any divisional walls, or even
fire-resisting partitions, naturally adds to the
probabilities of large fire claims as the whole
floor may easily become involved should a fire
break out, especially where there are the added
dangers of draughts, wood linings, etc."
Mr. J. H. Matthews.
4. Number of Assistants in Retail Shops, etc. —
The number of assistants employed in retail shops
— Drapers' shops for instance — is a good indication
of the size of the establishment.
As explained in paragraph 2, a large accumula-
tion of stock may carry a higher rate than a small
quantity in a proportionately smaller building.
Similarly, a Draper's Shop with a large number of
assistants, being necessarily a larger estabhshment
than one employing only two or three assistants,
may well carry a higher rate on account of its size.
The deduction as to the comparative sizes of
establishments from the number of assistants
employed is not apphcable to Warehouses, Cotton
Mills, Furniture Depositories, Corn Mills, etc. A
huge warehouse, for instance, may contain only a
comparatively small number of assistants. The
sizes of warehouses do not necessarily vary, even
4 COMMON HAZARDS.
approximately, with the number of assistants
employed, while, on a rough estimate, the sizes
of retail shops do.
Apart from the question of size, the risk of fire
may be said to vary directly as the number of
assistants ; each assistant is a potential causer of
fire through carelessness. Moreover, if a large fire
occurs in a huge Drapery Establishment a great
deal of time must perforce be taken up in saving
the lives of many assistants (probably women
for the most part) — time which could otherwise
be used in saving property from destruction.
5. Dwellings in Business Premises.— Where
there are dwellings in business premises, especially
at the top of high buildings, they constitute an
added risk, chiefly because of the possibility of
Fire Brigades having to spend time in saving the
in-dwellers instead of devoting all their energy to
the extinguishing of the fire.
6. Plural Tenancy. — Where there are several
tenants in a building this circumstance increases
the risk of fire. For the risk of arson — a crime
that we can hardly yet consider extinct — is
increased and there is a probabiHty of more care-
lessness. The watchful care and strict manage-
ment that might be exercised by a tenant in a
building occupied by himself alone is quite likely
to be vitiated by the carelessness or bad habits of
co-partners in the tenancy if there be such.
COMMON HAZARDS. 5
The placing and good care of Fire Extinguishing
Appliances throughout the building is rendered
more difficult and indeed almost too improbable
(as regards care) to warrant a discount to the
tenant who is to benefit by it in his Insurance
Further, where warranties are applied to an
insurance, it is extremely difficult for one of the
tenants to make certain that they are being duly
observed by other tenants.
7. Lack of Fire Brigade Assistance. — An item of
considerable importance in fixing the rate for a risk
is its distance from the nearest Fire Brigade
Station and the relative efficiency of the Fire
In this respect country mansions and country
factories are usually very unfavourably situated.
The distance to the station is often considerable
and the efficiency of the local Brigade far below
that of town Corps, while the supply of water
is often at an inconvenient distance from
It may be mentioned that this factor in Fire
Hazards counts for a great deal in the U.S.A. and
is one of the chief influences that tend to raise the
loss rates in that and other countries where large
areas are not well protected by Fire Brigades.
8. Night-work.— Night-work involves the con-
tinuous use of artificial light and often the use of
stoves or other means of heating— the risk of fire
is consequently increased.
Moreover irregularities, such as smoking,
arising from lack of full supervision, may occur.
The running of power machinery through the
night involves an extra risk of faulty lubrication
which may give rise to fire occurring through
In premises comprising several buildings where
there are fireproof doors, there is an added danger
that the latter may be left open unless they close
On the other hand, each worker may be looked
upon as tantamount to a night-watchman ready to
extinguish fire should it occur.
Balancing the " pro's " and " con's " there is,
no doubt, an additional hazard incurred by night
9. Moral Hazard.—'* Moral Hazard " means the
risk of the Insured or his assistants being so
dishonest as to set fire to his own premises, or
being so careless or having such bad habits as to
increase the danger of fire arising.
The term "Moral Hazard" should also be
understood as referring to the degree of intelligent
appreciation of the economic damage, done to
industry by fire, that is shown by the people in
the locality of the risk. The principles of Fire
Insurance are anything but well understood even
by the people of Great Britain : much less are
they appreciated in less civilised countries. It is
surprising how many people there are, even in this
country, who have a keen desire to get " something
back " in exchange for their Fire Insurance
Inefficient management of premises is akin to
Moral Hazard. A factory, for instance, that is
well managed will be clean (if cleanliness is possible
in spite of the trade carried on), neat and
One little test of good management from the
Insurance Company's point of view is the sweeping
up daily of all cuttings, clippings, shavings, saw-
dust, oily waste, etc.
10. Cleanliness of Premises. — Waste of all
kinds, shavings, sawdust, cuttings, cHppings,
waste paper, cotton waste, etc., particularly oily
cotton waste used for cleaning machinery, should
be swept up daily and either destroyed at once in
a safe manner or stored in a place at a safe distance
from the building. They are best placed in a metal
receptacle provided with a metal lid : the lid
should close automatically.
The regularity with which this is done and the
general cleanliness and orderliness of a business
place are tests of good management ; and a dirty
and untidy place is likely to be a bad risk.
Special reference to oily cotton waste is needed
because this matter is specified in the Chartered
Insurance Institute syllabus.
Cotton is a material that burns very easily
alone, and if saturated with oil, the danger of fire
is increased. A lighted candle, match, or taper,
and even sparks caused by friction in machinery
may easily start a blaze in a heap of oily waste.
Moreover the waste may take fire as a result of
spontaneous combustion. A heap of the material,
being made up of thousands of cotton threads
saturated with oil, each thread encircled with air,
is exceptionally liable to spontaneous combustion.
Hence the need for daily removal and storage in
metal receptacles or in the open.
11. Children playing with matches. — Children,
playing with matches, are responsible for a
relatively enormous number of fires. This is a
risk that could be reduced but hardly one that
can be offset against an additional rate of
12. Lights thrown down. — Smokers often
throw lighted matches down carelessly and without
watching where they go. Workpeople lighting up
lamps and gases, etc., do the same. In one year
alone 823 fires out of a total of 3,387 were caused
in London by this form of carelessness. This fact
shows how important a risk it is.
13. Treading on unused matches. — Treading on
unused matches and setting them alight by friction
COMMON HAZARDS. 9
is a source of many more fires due to gross careless-
14. Carelessness in depositing hot ashes.—
Carelessness in depositing hot ashes is also a cause
of destructive fires.
15. Smoking. — Smokers often throw down
Hghted matches without troubling to extinguish
them, or tap out red hot plugs of tobacco from
their pipes on to inflammable material, and this
again causes many fires.
16. Iron Gratings.— Iron gratings are a
dangerous feature, particularly when an accumu-
lation of waste paper or other rubbish has fallen
into the space below them. It very often happens
that the cellar windows just below the gratings
are broken and that the " undressed " beams of
the ground floor are within a few inches of the
window with the result that a lighted match
thrown through the grating may easily ignite the
waste paper and so cause fire to spread to the
timber of the floor with disastrous results.
This is a further instance of the benefit of
cleanliness and order.
17. Exposure. — Buildings are, in the majority
of cases, exposed to some risk of fire spreading
from neighbouring or adjoining buildings ; in the
congested parts of towns, or in narrow streets, this
risk may be very considerable. Of course the risk
of exposure can be considered almost negligible
if the building to be insured is of fireproof con-
struction. Flames issuing froni adjacent buildings
would find no nourishment from the outside of
such a building nor could they penetrate its
windows assuming that the latter were of wired
glass and properly fixed.
But as regards the majority of buildings the
risk of exposure is a very real one. It depends
upon : —
1. The construction of the buildings concerned
and of those near.
2. The respective heights of the buildings.
3. Their distance apart.
4. The proximity of openings reciprocally, and
whether they are directly opposite one
another, or at an angle, or overlooking.
5. The slope of the ground (in connection with
the flow of inflammable liquids or water).
A high building is more hable to communication
of fire to it from an opposing low building than a
low building from a high one, because the natural
direction of flames is upward.
A considerable slope of the ground from
neighbouring premises to the insured building may
have a great influence on the risk. For instance,
in case of fire in the building built on the higher
ground, a huge torrent of water may flow into the
lower building, causing water damage which would
have to be made good by the Insurance Company.
Or, should the building on higher ground be an
oil store, a garage or other kind of premises in which
oil or petrol are stored, burning oil might flow
towards the insured building and set it alight.
We have not only to consider exposure from
buildings that are contiguous or quite near : a
building even some distance away may endanger
the whole district if the latter is very con-
gested, and the prevailing type of construction
A common instance of exposure risk is that
caused by the proximity of hay stacks to farm
18. Exposure — Wooden Gutters. — Wooden
gutters are frequently a source of danger in con-
nection with exposure as they often communicate
fire from building to building. No doubt the
reader will have seen fire leaping along wooden
gutters and firemen striving to stem the tide as the
blaze approached other buildings.
This lateral spreading of fire along the gutters
can be prevented by the use of brick or stone
Wooden gutters entail the risk of exposure
particularly when they are overhanging a non-fire-
containing roof, or overhanging or near to windov/s
of an adjacent building ; for in such cases they may
catch fire from flames emitted from the roof or
windows of the adjacent building.
A remedy is to build the gutter inside a pro-
jecting parapet wall.
Gutters, spouts, etc. made of a composition of
asbestos and cement are now obtainable.
19. Exposure— Timber Gables.— Timber gables
and ornamental woodwork on the outside of
buildings are hazards similar to those mentioned
in the previous paragraph.
20. Exposure— Louvre-boards.— Some of the
buildings used for certain industries, breweries,
for instance, usually have part of the upper storey
open to the air for ventilating purposes, part of the
walls being only made of timber louvre-boards.
This form of construction is not a very serious
risk, apart from exposure, if proper precautions
are taken in connection with the trade carried
on ; but the risk of exposure would depend on the
adjacent buildings, and, under unfavourable
circumstances, would be serious.
Louvre-boards surrounded by the air, as the\'
are, would very quickly communicate flames
issuing from an adjacent building.
21. Exposure— Windows.— Windows and doors
are the weak spots in walls as regards exposure
unless the building stands a fair distance from all
others. Flames spreading from neighbouring
buildings will easily break ordinary windows, or
set their woodwork ahght, and force an entry into-
the building in either case.
The severity of this risk depends upon the
relative positions of the adjacent windows or other
openings. A window facing a solid brick wall does
not give rise to exposure risk unless the roof of
the adjacent building is lower (or at least near)
and not fireproof.
Remembering that flames naturally rise rather
than fall, it is obvious that the exposure risk from
windows is less to that building which has the
To be fire-resisting, windows should be con-
structed of wired glass set in hard iron frames.
The more windows there are in the side of a
non-fireproof building, the worse is of course the
22. Exposure — Roof Timbers. — ^The point where
the roof of a building is joined to the wall is always
a weak place as regards exposure ; for fire playing
on roofs at this point can usually penetrate the
small crevices and reach the roof timbers.
The remedy is to build the walls higher than
this point to a height which seems adequate having
regard to the size and occupancy of the adjacent
23. Exposure — Other External Woodwork.—
Wooden ventilators built on roof ridges may
easily be set alight by conflagrations in their
Mansard roofs and Dormer windows are mainly
•constructed of wood and are hazardous in the same
24. Too much window space. — Excessive
window space reduces the wall's power of weight
bearing. This does not matter in the case of a
shed building; but in the case of a building
having several storeys the weight of machinery
and stock on the floors may be a considerable
strain on the walls and, in case of a con-
flagration, the collapse of the walls would be
hastened if they were to a great extent composed
This is a constructional hazard apart from the
Exposure risk mentioned in paragraph 21.
Windows are easily broken by fire or by the
strong jets of water used by firemen, and when
broken they give entry to draughts of air which
facilitate the spreading of fire to the interior.
25. Timber Construction.— It is true that most
buildings, at any rate in this country, are brick or
stone built and slated or tiled (B.S.S.T.) ; but a
great deal of timber is nevertheless generally used
in the interior of most buildings.
Floor joists, floors, doors, window frames and
sashes, mantelpieces, picture moulding, skirting-
boards, hoists, staircases, etc., are usually or often
of wood, though an increasing number of these
things are nowadays being made of iron or other
The greater part of most roofs is also timber
The less timber construction the better, from
a fire risk point of view. In Canada and many
other newly developed countries it is responsible
for a great loss in national wealth.
Floor joists left uncovered, with " open finish "
as it is called, add to the risk of floors catching fire.
26. Wooden Linings to Walls and Ceilings. —
Wooden linings to walls and ceilings are frequently
to be found in warehouses, clothing factories, etc.,
where, for instance, cloth is stored from which
damp and dust must be excluded.
Such linings are very hazardous : they often
cover and conceal air spaces and, in case of fire,
they bum very easily, thus enabling the fire to
spread rapidly. They are usually nailed to battens
and it will be easily imagined how quickly they
bum, if once set alight, the woodwork being
practically surrounded by air.
In the case of ceiling linings the wooden boards
are nailed to the undersides of the floor joists, thus
forming air-pockets similar to those behind wall
In all such spaces defects in electrical wiring,
steam pipes or stove pipes may be concealed
and these defects may suddenly give rise to fire.
It is considered that air spaces, particularly
vertical hidden air spaces in walls and behind
surface finishings, many of them used for gas pipes
and electric wires, are exceptionally hazardous
features in building construction. They should at
least be provided with fire-stops at each storey.
If wooden linings are fixed to wooden plugs let
into the wall, it is important to make sure that
such plugs have not been thrust into gas pipes
or into fireplace flues, as in the one case a gas
explosion may result ; and in the other case fire may
ensue from the plug catching fire (after prolonged
charring) and communicating flames to the wooden
Linings not exceeding 6 feet in height are not
considered an excessive risk.
27. Timber Partitions.— Timber partitions, like
wooden linings, are very hazardous unless not
exceeding 6 feet in height.
Both linings and partitions, if they are to be of
timber, 'are best made of hard non-resinous wood
rather than match-boarding on timber-framing.
The latter may be httle better than firetraps. But
linings and partitions can now be made of asbestos
preparations and from a fire risk point of view
these are excellent.
28. Roofs. — Roofs to be fire-resisting should :
(a) Offer by their construction no important
fuel to a fire occurring in the building but
too often they are mainly built of timber
except for the slates.
(b) They should present no features of con-
struction which allow of easy communi-
cation of fire to them such as mansard
roofs, wooden ventilators, well-holes, etc.
(c) They should be of sufficiently strong
construction to resist ordinary falls of
material upon them from surrounding
(d) The external covering should be of non-
29. Imperfect Walls. — The walls separating
two buildings should be built up to and through
the roof to an adequate height, the comparative
risk of fire spreading from the one building to the
other being taken into consideration in deciding
Where the exposure risk is not considered
serious the ** party " or dividing walls are often
built only up to the roof and not through it, while
terrace dwellings are often separated only by walls
built as far as the top ceiling thus leaving a loft
or attic running the whole length of the terrace,
making the whole terrace practically one risk.
Such lofts are particularly hazardous : people
often store boxes, superfluous furniture or other
property in them and occasionally rummage about
in them with lighted candles, matches or tapers,
which may easily set fire to the house if carelessly
30. Projecting Shops. — Retail shops are often
built as annexes at the front of houses so as to take
advantage of suitable shopping positions without
altering the original building.
Such shops are usuall}^ of one storey only and
are consequently lower than the building at the
rear. The result is a considerable " exposure *'
risk of fire from the latter unless the roof of the
shop is of fireproof construction.
In case of fire in the rear building these pro-
jecting shops are often a serious obstacle to the
firemen especially if there are not separate entrances
to the two portions of the block ; for they (the
firemen) may find difficulty, or experience delay,
in reaching the fire through the shop, and they
might find their way of escape cut off in fighting
their way to the street from the rear.
31. Buildings not B.S.S.T.— In this country, at
least, buildings have attained such a high standard
that it is exceptional to find one that is not built
entirely of brick or stone and slated or tiled.
There are of course many exceptions, but as a rule
English buildings are B.S.S.T. (Cement concrete
is considered equivalent to brick or stone in this
connection, while tiles may be made of clay or
metal. Roofs covered with concrete are of course
as good or better than slated or tiled roofs.)
Such a type of building (B.S.S.T.) is therefore
taken as the normal by Fire Insurers and an
additional rate is often charged for constructions
that contain external materials that are more
easily damaged by fire.
Timber is obviously a poor fire-resisting material,
although it may be mentioned that hard wood at
least 9 in. thick offers considerable resistance to
fire. Corrugated iron can offer practically no
prolonged resistance to fire : its use in buildings
constitutes a bad hazard.
Portions of walls such as the walls of mansards
constructed largely of slates do not come
up to the standard implied in the expression
Internal timber such as wooden partitions,
doors, etc., and external timber used for gutters,
ornaments, doors, window frames, etc., while bad
features in themselves, do not preclude a building
from falling in the category B.S.S.T.
32. Exposed Iron-work. — Iron or steel girders
or joists are often used to support portions of
buildings, and the inexperienced student might
think that these at least are materials that should
■cause little anxiety to the Fire Insurance Company.
This is, however, far from being the case.
Cast iron when heated by fire and then suddenly
cooled, as it would be by the water used for
extinguishing purposes, cracks and thus endangers
the building supported by it.
Wrought iron turns and twists about under the
influence of heat thereby doing great damage to
the building supported.
" Iron and steel girders and joists are liable to.
" great expansion and contraction under the effects
" of fire and water, and they often become con-
" torted into the most fantastic shapes during a
'* conflagration unless properly protected by an
** efficient non-conductor of heat. This contortion
** not only utterly ruins the floors, but ofttimes
" results in the collapse of the walls also — in fact,
" in the total wreck of the entire building." *
It is exceedingly important that the iron
portions of the frames of buildings, girders, joists,
columns, pillars, etc., should be protected from the
effects of fire by being covered with a casing of
terra-cotta bricks at least 2 inches thick, concrete
or plaster at least one inch thick.
33. Staircases. — The prevention' of fire in a
building where there is anything inflammable is
largely a question of the prevention of draughts.
A staircase requires an open space from the ground
to the top ceiling of the building : as a rule it not
only makes all the floors accessible to a fire on any
one floor (and therefore all one risk), but it
necessitates the existence of a wide column of air,,
from the ground to the roof, which in case of fire
begins at once to flow quickly in an upward
* Report by the Chief Officer of the London Fire Brigade.
direction drawing in more air from all parts of the
building through open windows or doors. A
vigorous circulation of air is thus caused throughout
the building giving an enormous encouragement
to fire in whatever portion of the building it may
The hazard of a staircase is that it is a
prodigious air-feed. The fact that a staircase often
makes all parts of the building communicate with
one another is not by any means its worst feature :
it is the " air-feed " characteristic that necessitates
an increased rate.
Staircases, to be non-hazardous, should have
steps and landings constructed of brick, stone,
iron or cement concrete and should be enclosed
in walls of brickwork, masonry, or cement
concrete, all openings to floors being protected by
34. Hoists. — Hoists are hazardous in the same
way as staircases and should accordingly be
entirely enclosed with cement concrete not less
than six inches thick, or brickwork, or masonry ;
they should also have an iron or metal-covered
door to every opening.
A hoist constructed otherwise necessitates an
increased rate of premium.
35. Well-holes. — *' Well-holes are commonly
found as large openings through all the floors of a
building, surmounted by a glazed roof, the upper
floors forming galleries round the well, and in
Drapers' risks these have frequently led to rapid
and complete destruction of the premises." *
Such well-holes are indeed often found in large
Drapers' Shops, but are not confined to such risks.
They constitute a serious hazard for the same
reasons as staircases and hoists, but they combine
these serious features with the exaggerated
exposure of one part of the interior to another.
36. Internal Areas. — Internal areas are features
of risk often found in towns where land is expensive
and great economy of space has to be observed in
erecting buildings. Several buildings are grouped
round the four sides of a small open space, thus
obtaining light and a certain amount of ventilation.
This arrangement brings the buildings near
together and introduces exposure risk.
The larger the internal area, the less is the
exposure risk and vice versa.
Opposing windows in such areas may be
protected by fire-proof shutters to obviate or
mitigate the risk ; the windows should be of wired
glass ^set in iron frames and the walls built up
above the roofs of the buildings.
Internal areas are apt to have similar effects
on a fire to those caused by a staircase, inasmuch
as they may facilitate a tremendous up-draught
* Mr. W. Carter. " Royal.'
of air, the influence of which may be felt in all
parts of the building if a fire has reached con-
siderable dimensions in it.
37. The Smaller Openings in Floors. — There are
various unavoidable openings in floors of industrial
risks which are liable to increase the hazard of
fire unless properly protected. Such are, for
instance : —
Holes for ropes, belts, shafts, straps, steam-
pipes, gas pipes, water pipes, spouts and
Trap doors should not be more than four square
feet in area. The holes for ropes, belts, shafts,
etc, should be only large enough to admit such
things, while spouts or trunks should be con-
structed entirely of iron not less than one sixteenth
of an inch thick or No. 16 Birmingham wire gauge,
with an iron shutter of the same thickness to each
Shafts should fit closely in metal collars and
all pipes and tubes should be cemented round the
full thickness of the floor.
38. Firegrates. — ^The risk of fire, as understood
in Fire Insurance practice, is the risk of not always
succeeding in confining fire to the places intended
for it. Therefore a firegrate is in a sense one of
the centres of risk.
There is the risk of cinders falUng out .of the
grate on to wooden floors, oilcloth, or into clothes
drying in the fender.
Light material, as for instance straw or packing
paper, may be thrown on the fire, long flames dart
out and set woodwork round the grate on fire.
The grate may have been built in such a way
that the heat of the hearth gradually chars wooden
beams underneath it with the result that some day
the beams spring into flame endangering the whole
house. This is a frequently occurring cause of
fires in old mansions, old farmhouses, etc.
Skirting boards and mantelpieces and the sides
of fireplaces, being so near the fire, are best made of
metal or cement.
39. Disused Fireplaces. — Disused fireplaces in
houses are sometimes covered up with wood or even
paper. This is particularly hazardous because a
chimney may sometimes serve two fireplaces and
a fall of burning soot may arrive in the disused
fireplace and set fire to the wooden or paper cover
and so perhaps the whole house.
40. Corners and Ledges in Flues and Chimneys.
— Comers and ledges in flues and chimneys harbour
soot which may burst into flame and may set fire
to woodwork : they should be avoided as far as
possible in construction, or roimded off by the
addition of cement.
41. Chimneys "on fire."— -While on the
subject of chimneys and fire grates it may well be
pointed out that when an accumulation of soot in
chimneys and flues fires it often throws out a
volume of sparks. Frequently such sparks aided
by a high wind set fire to the roof timbers.
This is a serious item of risk, and it emphasises
the advisabihty of preventing accumulations of
soot in flues and chimneys by frequent sweeping,
by pargetting the sides of such chimneys and
flues, and by constructing them in such a way as
to avoid corners and ledges.
42. Pipe Stoves. — Stoves are a useful and
popular form of heating apparatus. There are
various kinds burning coke, coal, anthracite, etc.,
but they mostly have an iron pipe conducting the
smoke and gases through part of the building,
through a wall or roof, into the open air. Stoves
are very productive of fires and often constitute a
bad feature of risk.
Being so handy they are often carelessly
installed without regard to the risk of fire. They
should above all be placed on a sound and incom-
bustible base, such as a stone slab or sheet of metal,
and in such a position that the pipe is not
underneath combustible material which may fall
on to it.
There are the following risks in connection with
pipe stoves : —
I. Cinders falling on to combustible floor.
2. Soot accumulating in pipe, firing and falling
out, thus setting fire to combustible matter.
3. Combustible material falling on to the hot
stove or on to the hot stove pipe and thus catching
4. Radiation of heat from the stove setting fire
to adjacent woodwork.
5. Stove pipe setting fire to woodwork through
which it passes, as, for instance, where it passes
through floors or roofs or partitions.
6. Sparks from outside end of pipe setting fire
to woodwork on the outer side of the building.
The precautions to be taken are as follows :—
1. Stove should be placed on an incombustible,
sound and substantial base.
A large metal tray is a suitable base.
2. It is desirable that the pipe should have as
few or no bends in it where soot can easily
3. It should be placed in such a position that
combustible material cannot fall on it or on the
4. It should stand a reasonable distance from
5. Where pipe passes through wood or other
combustible material it should be protected by
passsing through a metal collar 2 in. or so larger
than the pipe itself, leaving J in. in diameter air
space between collar and pipe.
6. The outlet for smoke and gases should not
be dangerously near any woodwork on the outside
of the building.
7. Care should be taken that material which
produces long and unruly flames be not cast on to
the fire as fuel or to be destroyed.
8. Cracks in the pipe are very dangerous if
anywhere near to woodwork or other combustible
material and should be mended at once.
9. It is desirable though not essential that the
pipe should not be more than 3 feet in length.
10. The pipe should pass through a cemented
throttle when it penetrates woodwork.
Pipe stoves are often used in connection with
hot water pipes, and the above points should be
remembered when considering hot water apparatus
from a fire risk point of view.
43. Gas Stoves. — Gas stoves if properly installed
are fairly free from hazard except in incurring the
danger of gas explosions.
44.. Electric Radiators, etc.— Electric Radiators,
steam heated air and Steam Heating Installations
are good forms of heating arrangements.
45. Boiler Fires and Furnace Flues.— In con-
nection with furnaces and for industrial purposes
the same remarks apply as for pipe stoves as
regards the stove itself.
A much greater heat is, however, required in
furnaces for heating boilers, and the risk of fire is
The hazards are (i) defective setting; (2)
inadequacy of the shafts used for getting rid of the
waste gases of combustion ; (3) sparks flying from
the furnace ; (4) adjacency of woodwork or other
incombustible material ; (5) the drying of wood
on the boiler or near the furnace ; (6) accumulation
in the furnace room of inflammable material that
is intended for immediate destruction with danger
of hot cinders or ashes falling on to it.
For a building to be really safe from fire
boiler furnaces should not be in a non-fireproof
-compartment within the building, and if in a
fireproof compartment, or in a compartment
outside the building the boiler house should not
communicate with the building otherwise than by
a fireproof door.
Furnace flues should be lined with fire-brick
throughout for a distance of at least twenty feet
from the furnace.
46. Engine Houses. — " In how many risks
•erected a generation or more ago do we find engine
houses tucked away in odd comers, often in timber
partitioned-off compartments, frequently wood-
lined and dark, dependent on the feeble ghmmer of
a batswing burner for illumination. It is this
type of engine house which affords so many
opportunities for incipient fire. Its darkness leads
to the use of the surreptitious candle and offers
no inducement to the attendant to achieve that
scrupulous cleanhness which is so desirable.
Cleaning rags and waste are thrown about in odd
■corners, and the combustible character of its oil-
and-grease-soaked environment renders its presence
within the main risk a menace which I think we
sometimes fail to value at its true worth.
In our modern risks it has become quite usual
to find the engine house a self-contained shed risk,
well lighted from the roof, an airy room with glazed
brick walls and tiled floor — a very miracle of
cleanhness. We find in evidence a metal cabinet
lor the necessary oil, a metal tin for cleaning
waste, and every sign of care."
Mr. W. Carter, " Royal."
47. Hot Water Heating Apparatus.—" A low
pressure hot water system is one which is fed from
a tank fitted above the highest part of it and open
to the atmosphere. In such an apparatus the
neatest heat attainable, even in the neighbourhood
of the furnace, is the ordinary boihng point of
water (212° F.) plus the shght extra temperature
"due to the weight of the column of water between
it and the tank. In a high pressure hot water
system, however, this hmitation does not exist.
The water is contained in an hermetically sealed
circuit, the temperature attainable being regulated
by a relief valve, weighted so as to blow off at a
given pressure." (" Post Magazine ").
In a low pressure hot water apparatus the
maximum temperature attained in the pipes is in
practice only 160° F., although a temperature of
212° F. is theoretically possible.
High pressure hot water pipes may reach a
temperature of 392° F.
Fires have been known to be caused by hot
water pipes remaining in contact with light
inflammable material, or even woodwork, for a
time, but the risk is not great. The chief source
of danger is in the furnace and boiler room, and
as to this the remarks in paragraphs 42, 45 & 46
It is desirable that the furnaces should be in
separate chambers of a fire-resisting character
communicating with the building to be heated
only by a fire-proof door. This, however desirable,
is not always or even often the case, but in some
classes of risk is imperative. In a motor garage,
for instance, it would be highly hazardous to have
the furnace in the same compartment as vehicles
48. Gas Lighting. — Gas lamps (by which term
is commonly meant lamps burning coal gas in air)
entail the following hazards : —
I. In shop windows they are liable to set fire
to hanging drapery, Christmas decorations, or
other flimsy articles, unless care is exercised to
prevent their doing so.
2. Where movable or swing brackets are used
there is the danger of their being pushed too near
woodwork or other inflammable material.
3. Even when fixed they may be too near to
woodwork (wooden hnings for instance) or other
inflammable material. In this case the woodwork
should be protected by a piece of metal fixed to the
woodwork by long bolts and nuts, thus providing a
clear air space of at least 2 in. between the wood
and the metal. If metal plates are nailed or
otherwise fixed close to woodwork they only
conceal charring without preventing it.
The above method of protecting woodwork
from heat is useful of course whether the heat
comes from a gas, a stove, or a furnace, etc.
4. A frequent source of fires is the blowing of
curtains on to naked gas lights. A house window
is perhaps left open on a windy night and the
flimsy curtains flap about the gas with disastrous
results. For this reason the gas should be protected
by a glass globe or a strong wire cage.
5. The heat given off by the burner may be
intense enough to char and eventually to set
alight a wooden ceihng if there be one above it and
near it. This danger is more acute if the gas is
an incandescent gas and particularly if it carries
an upright vertical mantle : the inverted mantle
is perhaps less dangerous in this respect because it
has metal fittings above it which carry off the heat
to some extent.
This risk should be prevented by the suspension
of a metal reflector, of suitable size, above the
In the incandescent gas the mantle is made
luminous by the heat of a bimsen burner which is
very much more intense than an ordinary gas
light and greater precautions are therefore
6. Gas lamps are sometimes used in which the
gas is led to the lamp through a flexible rubber
tube. This is a distinct hazard: these tubes
easily get split or slack and there is considerable
danger of a big escape of gas, and therefore of gas
explosion. The explosion of coal gas in this way is
of course a risk that is generally covered by Fire
Further the rubber tubmg may accidentally be
In connection with incandescent lighting,
" There are in use many systems whereby the
pressure of the gas as dehvered by the mains is
raised, so that the gas issues at the bunsen burner
at an increased velocity and takes with it a pro-
portionally increased amoimt of air with corre-
sponding intensity of heat.'*
Mr. L. T. Healey, " Royal."
Other things being equal a high pressure
incandescent gas, of course, needs safeguards such
as metal reflectors or metal shields to woodwork
more urgently than an ordinary burner.
49. Paraffin Lamps.— Standard Paraffin Lamps
are easily knocked over and many household fires
are caused in this way. The same appUes of
course to table lamps. When knocked over they
do not necessarily explode but burning paraffin
runs about the floor setting fire to floor coverings
Portable paraffin stoves cause fires in the san^e
Paraffin lamps with containers made of glass
are particularly hazardous on account of the risk
of the glass breaking.
There is also the danger of explosion with
paraffin lamps. The latter should be kept
scrupulously clean and the wicks should be tight
50. Candles.— Candles cause a great number of
fires. They are so cheap that they are used by the
million; they are so handy that thousands of
workmen use them for all sorts of jobs where light
is required in dark places ; they are so round and
yet so inflammable that if knocked over they run
along the floor and keep ahght ; and they are
mostly used naked.
Tapers are as bad.
V. - —
24 COMMON HAZARDS.
Common instances of fires caused by Ughted
candles and tapers are as follows :—
(a) Workmen using them carelessly in the
cocklofts of houses.
(b) People reading by candle Hght in bed and
falling asleep, perhaps knocking the candle
(c) Grease on geared machinery being ignited
by candle flame.
(i)^Children playing with candles.
51. Acetylene Gas.— Acetylene is more Uable
to'explode than coal gas, and it is heavier risk if
for this reason alone.
The risks attending coal gas lights apply also to
Acetylene, but to a greater extent, unless the user
is more careful, as he mostly would be, than with
the more familiar luminant.
The generating apparatus must be kept in
the open or in a separate building used for no
other purpose. Acetylene being one of the most
explosive and inflammable gases known, its
generation is to be absolutely prohibited in a
building used for habitation or industrial or
52. Petrol Lamps.— There are now many
patterns of burning lamps that burn petrol vapour
and some of these give a light equal to 3CX) candle
power. They are comparatively cheap and not
particularly risky, so that it is likely that their
use will increase considerably.
53. Gas Engines. — Gas Engines are machines
the effectiveness of which depends upon the timely
explosion of a mixtmre of coal gas and air within a
metal container. It is obvious then that they may
become dangerous if for any reason the explosion
takes place in some other than the appointed place.
There is unfortunately a liability for the mixture
to explode in the exhaust pipe. Partly for this
reason and partly because the exhaust pipe is
peculiarly liable to become hot in any case, that
is a portion of the engine to which attention
should particularly be paid by the Insurance
A high degree of heat is necessarily maintained
within gas engines, and consequently there is a
danger of their external parts (but particularly
the exhaust pipe) becoming hot enough to ignite
inflammable material that is in contact or juxta-
position. Care should therefore be taken in this
respect as also in seeing that the engine is satisfac-
torily erected in a suitable position.
In connection with gas engines there are, of
course, the dangers inherent in using for any
purpose at all such an explosible gas as coal gas.
54. Hazardous Goods. — The foUowing are
hazardous goods: —
Bi-sulphide of carbon.
Gunpowder and other
Vegetable and lamp blacks.
Matches (stored wholesale).
Mineral oils and their liquid
Nitrates and chlorates of
sodium and potassium.
Rubber and gutta-percha
Spirits, not rectified.
Vegetable fibres and grasses.
Textile mill waste.
1. State reasons for considering a five-storeyed
warehouse to be a heavier risk than a three-
storeyed warehouse otherwise of similar nature.
2. What bearing on the Fire Risk has the Cubical
Capacity of a building? State reasons for
3. Why is information as to the number of assistants
in a large Drapers Shop considered useful in
estimating the Fire Risk ? Give at least two
4. Indicate as many dangers as you can that are
entailed by Plural Tenancy.
5. Why do you consider that Night- work is likely
to increase the risk of Fire in a factory ?
6. Indicate in a few words what instructions you
would recommend the Manager of a country
Saw Mill to issue regarding the cleanhness of
7. How does the accumulation of shavings, oily
waste, paper and other refuse on the floor of a
factory increase the danger of fire ?
8. A low pressure hot water apparatus having been
installed in a blouse factory, to what parts of
the system would you pay special attention
when inspecting the installation ?
n What precautions do you consider nece^ary m
^ connection with the introduction and use of a
low pressure hot water apparatus in a factory .
10 Indicate, in a few words, five commonly occurring
causes of Exposure Hazard.
TT Fxnlain why vou consider the wooden linings in a
"■ ^ Srui or factory to be a serious feature of
X. Write a short paragraph or two on the question of
''• "^"oof s in re^atTon to tL effect of their construction
on Fire Hazards.
13. Describe the main features (^romj.jlrejnsnrer's
^ point of view) of a perfect party wall.
14 Which of the following supports for floor joints
give rise to the least fire risk :—
(i) Iron columns (uncovered).
gSSuimber pillars, xr thick.
How would you suggest any of these could be
improved from the point ,of view of the Fire
Ts Describe the bad features of internal are^ with
'5- ° reference to their effect on the Fire Risk of
buildings surrounding them.
16 What precautions would you recommend should
'^- ^ be observed in installing a pipe f "J^ * ^^ ^^^
purpose of heating water for a low pressure
hot water system ?
Tf , stove Dine is to pass through a wooden
'7- "-partWon Xt speciafprecautions would you
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